\input zb-basic \input zb-matheduc \iteman{ZMATH 2016f.01191} \itemau{\'Aroksz\'all\'asi, Eszter} \itemti{I learned a lot and it did not go": development of the combinatorial thinking in the secondary school.} \itemso{Fritzlar, Torsten (ed.) et al., Problem solving in mathematics education. Proceedings of the 2015 joint 17th conference of ProMath and the 2nd GDM working group on problem solving, University of Halle-Wittenberg, Germany, September 3--5, 2015. M\"unster: WTM-Verlag (ISBN 978-3-95987-012-2/pbk; 978-3-95987-013-9 /ebook). Ars Inveniendi et Dejudicandi 6, 23-32 (2016).} \itemab Summary: Thought combinatorics plays a dominant role in Hungarian mathematics curriculum for Grades 1--12, a lot of Hungarian students have difficulties with the combinatorial concept and combinatorial problem solving. In this paper I would like to report about a school experiment in a Hungarian secondary school Grade 8. The main aim of the experiment was using of different representations in combinatorics teaching and applying immediate and continuous feedbacks in combinatorics problem solving. The result of experiment proofs that both factors important effective teaching of combinatorics. \itemrv{~} \itemcc{K20 D50 D40} \itemut{combinatorial thinking; combinatorics; problem solving; feedback} \itemli{} \end